This invention relates to apparatus for use by locksmiths and more particularly concerns apparatus for the orderly and controlled disassembly of interchangeable core locks.
In cylinder locks of conventional design, a cylindrical key-receiving plug having a first series of radially disposed channels is rotatably mounted within a cylindrical bore in a housing having a second, matching series of channels, known as "pin chambers." The pin chambers are in coaxial alignment with the first series of channels, and open upon said bore. The opposite extremities of the pin chambers, furthest from the bore, are closed. Each pin chamber is adapted to confine a coil spring in abutment with said closed extremity, and a driver pin which is urged toward the key-receiving plug by the spring. In many embodiments of such locks, one or more spacer rods may be positioned between the spring and driver pin within the pin chamber. The combined sequence of different spacer rods constitutes a code for opening the lock.
In certain types of cylinder locks, generally referred to as interchangeable core locks, the portion of the housing of the lock which contains the plug and pin chambers is part of an assembly, known as a "core" which is slidably removable from the lock when released by a control key. The controlled removeability of the core is desired by institutions where a high turnover of employees necessitates a periodic change of locks to maintain security. Cores of several different codes may be kept by the institution, all keyed for a single control key but requiring different operating keys to open the locks. On occasion, the keys may be lost, and a locksmith is required to disassemble the lock to ascertain the code and make a replacement key.
The core further contains the cylindrical bore which houses the key receiving plug, and the wall of said bore has a series of apertures axially aligned with the first series of channels and diametrically opposed thereto. The extremities of the pin chambers furthest from the bore are closed by means of friction-fit discs. By virtue of such manner of construction, the springs and driver pins can be extruded from the pin chambers of the removed core by driving a punching tool through the apertures in the wall of the cylindrical bore. In such disassembling techniques, the sequence of the removed components is: friction disc, spring, spacer rods and driver pin. The removed components must be maintained in proper arrangement for individual measurement and subsequent re-insertion into the core. Because of the small size of the components and the necessary precision of their positioning, their handling is difficult.
It is accordingly an object of the present invention to provide apparatus for the precisely controlled removal of components from the pin chambers of removable cores of cylinder locks.
It is another object of this invention to provide apparatus as in the foregoing object which is easily operated and has securing means to prevent inadvertent movement of the core during disassembly.
It is a further object of the present invention to provide apparatus of the aforesaid nature of rugged and durable construction amenable to low cost manufacture.
These objects and other objects and advantages of the invention will be apparent from the following description.